new rear end?

[qwikz28]

http://www.ls1tech.com/forums/showthread.php?t=781110

anyone have any thoughts on this rear to replace my 12 bolt? it will only cost me about a couple hundred bucks more than what i can sell my 12 bolt for and what it will cost to repair the gear whine in it. remember, i rarely go to the track. i just want something that will affect my handling and drivability as little as possible and not have to worry about getting stranded one day. heres my view on it:

advantages:
stronger
weighs MUCH less
better TA design

disadvantages:
still new design, unsure of reliability and performance
possible clearance issues (although he said there are none)
worth the extra money?

what do you guys think?

[procamaroz28]

jake that looks nasty, its gotta be stronger and for sure lighter, if you ask me its a no-brainer go for it... i would

[98tadriver]

my 12 bolt whines some, isnt that normal?

[qwikz28]

my 12 bolt whines some, isnt that normal?

mine is louder then my exhaust at highway speeds. heads/cam ls1 with 4.10s... that can't be normal

[JSPERFORMANCE]

a small amount of gear whine is acceptable with aftermarket gears but if it is loud enough that it is really noticeable there is probably a problem with a bearing or the gear tooth contact surface

[qwikz28]

a small amount of gear whine is acceptable with aftermarket gears but if it is loud enough that it is really noticeable there is probably a problem with a bearing or the gear tooth contact surface

do you mind if i ask your personal opinion on that rear i posted up about? either way, i was gonna bring the car to you to either fix my current rear or have that one installed. does anyone know anything about custom fabircated rear ends?

[JSPERFORMANCE]

I wouldn't waste the money if you already have a 12 bolt, the difference in strength between the two is minimal and the ford rear has its fair share of issues as well. They are only as good as the center section you put into it. I left my 9" scattered all over Atco and it had a nodular chunk, steel spool, billit yoke, billit support, etc, etc.. Didnt make much of a difference when it was being shoveled into the trash can next to the starting line..

[qwikz28]

I wouldn't waste the money if you already have a 12 bolt, the difference in strength between the two is minimal and the ford rear has its fair share of issues as well. They are only as good as the center section you put into it. I left my 9" scattered all over Atco and it had a nodular chunk, steel spool, billit yoke, billit support, etc, etc.. Didnt make much of a difference when it was being shoveled into the trash can next to the starting line..

its not really the strength i'm going for. its certainly the weight, torque arm design, and drivability i'm going for. i really can't deal with the clunks and whining of this rear. but then again, i'm not really certain the clunking is coming from the rear. i'm so confused...

[Tru2Chevy]

Jake, just drive the car down to Josh's shop and let him stick it on a lift and check it out.....

- Justin

[qwikz28]

Jake, just drive the car down to Josh's shop and let him stick it on a lift and check it out.....

- Justin

yeah, i was supposed to do that last week but i realized i forgot to call him and didn't wanna impose like that. whats holding me back is that i'm extremely indecisive on which direction i wanna head on this issue. it would be unfair to have my sitting on his lift for weeks while i sit and contemplate what i want to do with my car. the only thing i know is that i'm sick of whines, clunks, vibrations, and ABS lights. i'm willing to buy a new rear if thats what it takes. this fab 9 inch looks promising and the idea of starting new as opposed to this used 12 bolt sounds extremely appealing right now.

[Tru2Chevy]

No need to leave the car there for weeks, just take it down and have him figure out what's wrong with it. I'm sure he won't have a problem with helping you find the problem and fix it. If it turns out that your 12 bolt really is causing all the problems, he can either fix it or replace it for you.

- Justin

[qwikz28]

No need to leave the car there for weeks, just take it down and have him figure out what's wrong with it. I'm sure he won't have a problem with helping you find the problem and fix it. If it turns out that your 12 bolt really is causing all the problems, he can either fix it or replace it for you.

- Justin

i think i'm gonna schedule an appointment to have him lift it up and check it out. maybe i won't have to leave it and that can give me the winter to research and decide which direction to go with it. i would just love to have some unbiased info on that rear. it looks promising.

[JSPERFORMANCE]

The weight between the 12 and the ford rear isnt all that much different. Your car is probably a bit too heavy to go with the aluminum center section so the weight savings would be minimal.

[WildBillyT]

IMO, and I could be way off:

I'd be wary using this on the street because of the wall thickness of the housing. Not in terms of strength, but because it looks thinner than a stock casting and as such probably doesn't dampen as much gear noise. Yes, properly installed gears shouldn't make noise, but if you end up with a set that does it might be worse than what you have now.

[qwikz28]

in that case let the diagnostics begin, we're gonna fix that 12 bolt :)

[Mike]

haha jake, josh is gonna be doing the same to my 12 bolt, when he was driving my car he told me we HAVE to look into it...... it was LOUD

[qwikz28]

haha jake, josh is gonna be doing the same to my 12 bolt, when he was driving my car he told me we HAVE to look into it...... it was LOUD

mine is damn loud too. along with some clunks and bangs from the undercarriage. i think josh is gonna learn to hate me soon... :)

[NightRydaSS]

mine is damn loud too. along with some clunks and bangs from the undercarriage. i think josh is gonna learn to hate me soon... :)

clunks and bangs??? did u check out ur U-Joints? Mine are worn a lil and i have some clunks. The bangs are b/c my exhaust hits my panhard bar upper mount (need a relocation bracket).

[qwikz28]

u-joints? its not an exhaust clearance issue i know that, i think it has something to do with my diff and axles.

[Tru2Chevy]

u-joints?

Your u-joints are at either end of your driveshaft....they look like this:

http://northwestfab.com/images/NWF%20006.jpg

If there is play in them, that will make plenty of noise while driving, and they'll need to be replaced ASAP.

- Justin

[qwikz28]

Your u-joints are at either end of your driveshaft....they look like this:

http://northwestfab.com/images/NWF%20006.jpg

If there is play in them, that will make plenty of noise while driving, and they'll need to be replaced ASAP.

- Justin

hmm.... DS is used. maybe thats it. what kind of noise would they make if they were bad? like say a whining noise?

[Tru2Chevy]

hmm.... DS is used. maybe thats it. what kind of noise would they make if they were bad? like say a whining noise?

Usually more of a clunk/bang. Although I suppose the bearings in them could whine.

- Justin

[qwikz28]

Usually more of a clunk/bang. Although I suppose the bearings in them could whine.

- Justin

eff it... i'll replace it anyway. gotta drop off the car at josh's soon

[Tru2Chevy]

eff it... i'll replace it anyway. gotta drop off the car at josh's soon

Usually you can tell if they are bad just by reaching underneath and trying to rotate the driveshaft by hand while the car is parked. If you can twist it, then you have slop in the driveline, and that slop could be caused by worn/bad u-joints.

Josh will check all that stuff I'm sure though.

- Justin

[JSPERFORMANCE]

usually u joints will make a clunk or vibration not usually known to make any whining noises.

[camaro2you]

I have a clunk in the rear of car when i go over bumps and i have checked everything possible, could it be the u joints?

[JSPERFORMANCE]

Not likely, they usually make noise when you go in and out of gear. Clunking over speed bumps soundls like something else could be bad.

[DrivenZ28]

I have a clunk in the rear of car when i go over bumps and i have checked everything possible, could it be the u joints?

I had a similar problem, it turned out to be my rear lower control arm bushings...they were trashed. I got some new tubular control arms with poly bushings and the car rides like a dream now...no noise.:nod:

[camaro2you]

I had a similar problem, it turned out to be my rear lower control arm bushings...they were trashed. I got some new tubular control arms with poly bushings and the car rides like a dream now...no noise.:nod:

Actually turned out to be the drivers side caliper bracket worked itself loose, the locktite must not of grabbed enough threads.

[DrivenZ28]

Actually turned out to be the drivers side caliper bracket worked itself loose, the locktite must not of grabbed enough threads.


Ah yes, that will do it...glad to hear you figured it out! Mine haunted me for months before I finally did something about it.

[qwikz28]

i'm bumping this up because i feel like i would like to buy this unit. after contemplating my options, i realize that i'm just not happy with the 12 bolt. the idea of a lighter rear makes sense.

i don't intend on drag racing much or very hard if i do so i believe i should be fine with an aluminum center section. and people are saying this rear is quiet which is one of my primary concerns. is there anything else i should look for or should i bite the bullet and buy the rear?

[bad64chevelle]

Did you try to fix your 12bolt at all?

[JSPERFORMANCE]

Did you forget what I told you? The aluminum center section is really only for lightweight purpose built race cars. With a iron center section the weight savings are minimal if any at all. The m9 uses its own torque arm assembly and does not use any of the stock arm geometry. Also there are no provisions to run the stock rear sway bar. You already have a 12 bolt, the problems you are having are most likely a gear issue, which can happen to any style rear differential. Do what you want but you will definately be spending alot more money and alot more agg going to the M9 rather than repairing the 12 bolt you already own.

[qwikz28]

no, i didn't try repairing the 12 bolt yet. i just have a bad feeling about this rear for some reason. it needs a lot of work cause there is alot of different noises coming from my undercarriage.

thanks josh, i was hoping i could get away with the aluminum but it would be wise to trust your experience. i hope your up for the task cause i'm dropping my car off as soon as my GF finishes her lab in two weeks. :rock:

ps- josh, a little off topic but do you do exhausts? for example if i wanted a muffler welded in?

[JSPERFORMANCE]

Yes I can weld a muffler in for as well. Just let me know when you want to drop it off..

[qwikz28]

Yes I can weld a muffler in for as well. Just let me know when you want to drop it off..

i'll let you know when i know for sure. i've been trying to drop it off since last year, its just one thing after the other though...